Check Your Reproduction Throttle Cable Twice

I had this same problem. I now have ordered a cable from a new A body that I know is 4" longer so I am hoping to just put a loop in the cable somewhere. If that new cable you purchased physically works you could just try to get a new circlip that fits the new cable.
The ball end on my new cable is too big to fit in the gas pedal, but if the other cable I ordered doesn't work I'll try to file the ball down a bit.